Sustained Benefit from Treatment of Polyarticular Juvenile Arthritis with a Biologic Agent

Biologic agents are a new class of drugs used to treat rheumatic diseases since 1998. Biologics are genetically engineered products directed to block specific immune pathways, such as cytokine signaling. These agents have dramatically improved treatment of chronic inflammatory arthritis. Etanercept (Enbrel®) was the first biologic agent used in rheumatology; it blocks the actions of a proinflammatory cytokine, tumor necrosis factor alpha (TNFα). Etanercept was shown by members of the Pediatric Rheumatology Collaborative Study Group (PRCSG, a US and Canadian pediatric rheumatology research consortium) to be a safe and effective treatment for children with severe juvenile rheumatoid arthritis (JRA).¹ Although juvenile idiopathic arthritis (JIA) is the preferred classification system for pediatric patients with chronic inflammatory arthritis of unknown etiology (see AAP Grand Rounds, June 2006;15:70OpenUrlFREE Full Text ),² the work cited in this study originated prior to 2000 and, therefore, uses the older JRA terminology.

The PRCSG initially examined the effects of etanercept in children (ages 4–17 years, mean 10.5 years) with JRA who had at least 5 active joints; this included …